Siege of Pilsen

The Siege of Pilsen occurred from 19 September to 21 November 1618 during the Thirty Years' War. In the first action of the war, a 20,000-strong Bohemian Protestant army under Ernst von Mansfeld captured the Bohemian city of Pilsen, enlarging the Bohemian revolt against the Holy Roman Empire.

Background
At the start of the Bohemian Protestant revolt against the Holy Roman Empire in 1618, the Bohemian nobles offered the crown to Frederick V of Palatinate and the rulers of Transylvania, Savoy, and Saxony, hoping to form a defensive alliance. Transylvania and Saxony decided to remain neutral, but Duke Charles Emmanuel I of Savoy responded to the Bohemian call for help swiftly, sending 2,000 troops under Ernst von Mansfeld and financial aid to assist the Bohemians. Von Mansfeld was soon named commander of all of the Protestant Bohemian forces.

Siege
Many Catholic priests and nobles began to flee the country as the revolt spread, and thousands of Catholic refugees took refuge in the city of Pilsen, which was well-prepared for a lengthy siege. Mansfeld decided to quickly take the city before it could be reinforced by other Catholic forces; the defenders suffered from a lack of gunpowder, and the fortress was undermanned. The small force of defenders was able to withstand siege and bombardment until 21 November, when the walls were breached and the city was stormed. Von Mansfeld then demanded 120,000 guldens as war reparations in exchange for not burning the city to the ground. The capture of Pilsen was the first action of the Thirty Years' War, and the Catholic forces rallied over the next two years and prepared a counterattack.